Local methylprednisolone delivery using a BiodivYsio phosphorylcholine-coated drug-delivery stent reduces inflammation and neointimal hyperplasia in a porcine coronary stent model

Phosphorylcholine (PC)-coated stents have shown excellent blood and tissue biocompatibility in porcine coronary arteries. The purpose of this study was to determine the efficacy of local methylprednisolone (MP) delivery using PC-coated stents to inhibit inflammatory response and in-stent neointimal hyperplasia in an overstretched porcine coronary model. BiodivYsio (Biocompatibles, Farnham, Surrey, UK) PC-coated drug delivery (DD) stents and DD stents loaded with a high dose of MP (269 microg) were implanted in the coronary arteries of 20 pigs with a balloon/artery ratio of 1.2 : 1. At five days the peri-strut inflammatory response score and thrombus score of the MP-loaded DD stents were lower than in the control stents. The neointimal hyperplasia of MP-loaded DD stents was significantly reduced (0.80 +/- 0.10 versus 0.48 +/- 0.10 mm(2), p < 0.01). At four-week follow-up, the inflammatory response of MP-loaded stents was lower than the control stents, but without significant difference. The MP-loaded stents showed decreased peri-strut arterial injury and in-stent neointimal hyperplasia (2.42 +/- 0.87 versus 1.62 +/- 0.71 mm(2), p < 0.05). It is concluded that local vascular delivery of a high dose of MP from PC-coated DD stents could effectively decrease inflammatory response and thrombus formation after oversized stent deployment and result in a significant reduction of neointimal hyperplasia.